ASSESSMENT OF FIBER ORIENTATION IN REINFORCED-CONCRETE USING FOURIER IMAGE TRANSFORM

In this study, ribbon-shaped amorphous cast-iron fibres were used to r einforce a concrete matrix. X-ray photographs have been taken to detec t fibres ill situ. Their orientation has been investigated by automati c image analysis methods. However, this measurement should not he infl uenced by the digitization on the square frame of the analyser. For th at purpose, the Fourier transform was used rather than the rose of dir ection method. This analysis revealed the transverse isotropic nature of the spatial arrangement of these fibres, whose axis of revolution c orresponds to the concrete casting axis. Such a morphological characte rization of the fibre-reinformed concrete reveals its mechanical behav iour.